Small fixes around the code

1) Missing member initialization in constructor.
2) More explicit evaluation precedence in an expression.
3) Typos in comments.

BUG=


Review URL: https://chromiumcodereview.appspot.com/12316136

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@186355 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/content/browser/web_contents/web_contents_impl.cc b/content/browser/web_contents/web_contents_impl.cc
index 7161798..f7bee534 100644
--- a/content/browser/web_contents/web_contents_impl.cc
+++ b/content/browser/web_contents/web_contents_impl.cc
@@ -303,6 +303,7 @@
       temporary_zoom_settings_(false),
       content_restrictions_(0),
       color_chooser_(NULL),
+      message_source_(NULL),
       fullscreen_widget_routing_id_(MSG_ROUTING_NONE) {
 }